Automobile manufactures require that non-carpeted flooring material have good abrasion resistance, scratch and mar resistance, low gloss, and grain definition, while being colorable, durable, and able to withstand large temperature changes without failure. In addition, automobile manufactures require that the flooring material has a low modulus (elasticity) for ease of installation into a vehicle.
Known non-carpeted flooring materials may be manufactured from blends of impact modified polypropylene and high melt strength polypropylene (partially crosslinked). The impact modified polypropylene creates flexibility to facilitate installation into a vehicle and contributes to low gloss, while the high melt strength polypropylene facilitates scratch and mar resistance, and provides adequate strength during a thermoforming process. However, these known flooring materials have a narrow window of temperature range for thermoforming. High crystallinity of the material leads to sharp drop-off in melt strength during the thermoforming process. In addition, these known flooring materials also significantly increase in gloss as forming temperatures are increased which does not meet automobile manufactures requirements.
Thermoplastic polyolefin (TPO) compositions for use in low gloss sheet that can maintain low gloss have been developed for reduced gloss automotive applications. TPO blends of one or more ethylene/α-olefin elastomers and one or more polypropylenes to make fabricated articles or products, e.g., instrument panels, door panels, and non-carpeted flooring are known. See, for example, U.S. Pat. Nos. 6,372,847; 6,680,361; 7,750,104; 8,304,496; and 8,431,651. These blends and products demonstrate many desirable qualities, e.g., good to superior melt strength and processability, moldability, impact and mar resistance, modulus, elasticity, and the like. However, for some applications, these TPO compositions are not well suited for thermoforming and/or the providing an acceptable gloss level to fabricated articles made therefrom.
It would be desirable to have an elastomer composition which can be thermoformed into non-carpeted flooring applications having improved abrasion resistance, reduced gloss, and low odor and emissions.